Changing Stars
by BloodAndDiamonds
Summary: Due to a transporter malfunction at the wrong place in the wrong time, Spock awakens to find himself in the body of the world's only Consulting Detective. Pre-slash Kirk/Spock John/Sherlock


Jim's really not sure how this happened. All he knows for certain is that one moment there's an ion -or magnetic, the details have blown from his mind at the sight of _this_- storm at the end of shore leave, and suddenly the transporter is picking up two signals from two different _centuries_, let alone countries. His communicator is beeping constantly, the transporter is ready to cough up the mangled mess that is likely the transmitters of the two signals, and Scotty's too damn exhausted to even think about leaving his quarters today.

Jim decides, perhaps a little cruelly, that he's going to confiscate Scotty's supply of alcohol for the next year if he manages to pull his First Officer back to the transporter pad the way he left it.

And then suddenly, as though the storm had never existed in the first place, the transporter calms and separates the two signals, depositing the second signal back in its time and place and beaming up his first officer from the Starfleet Academy.

Only, when his first officer materialises on the transporter pad, Kirk knows immediately that it's not his Spock.

His Spock, although he had constantly reminded Jim that as a Vulcan he was lacking in emotions, had always been able to hide the few surges of emotions he had through sheer force of will. His only tell was his eyes. After two years with the Vulcan as his first officer, Jim's fairly certain he can consider himself an expert on guessing Spock's state of mind just with a simple glance.

But this, this is all _wrong_. Whether it's a Spock from an alternate universe -and isn't he just getting _sick_ of this scenario- or someone else completely, Jim isn't sure, but the Vulcan on the pad certainly is _not his_ first officer. His lips are parted slightly, eyes narrowed as he takes in the transporter room, and his posture is slack, as though he's been standing around complaining of boredom. His eyes gleam in the lights of the transporter room, as though his mind is going a hundred miles a minute and this is a fantastic new puzzle. Jim rather thinks he looks like a child given a new toy.

The ensign next to Jim clears his throat awkwardly, and Jim snaps his gaze up to Spock's eyes as the Vulcan straightens, looking annoyed at the distraction to his analysis of the room. Jim tries his hardest not to be freaked out at the display of emotion. Calmly, and fully aware of the not-Spock's intense gaze on him as he moves, Jim opens his communicator.

"Kirk to sickbay." The reply is almost _too_ quick.

"Yeah?"

"Bones, get your ass up to the transporter room... You er, might need to take a look at this." And then, ignoring the "damnit" that surely comes from his CMO, Jim closes his communicator and looks back at the not-Spock on the transporter pad.

"Fascinating." It's Spock's voice, and yet it's full of too much interest and curiosity for it to really be Spock. Jim frowns, and Spock moves off the pad. He stumbles, almost as though his limbs are slightly too long and too heavy for him to manoeuvre properly, and then straightens again, his hands moving to his neck and grasping nothing but air before they fall to his sides again with a brief snort of displeasure. Jim wants to scream. Or cry.

"So, Spock." A snort of impatience leaves the Vulcan's lips.

"Oh please, you and I both know that I'm not your first officer." There's a smirk on not-Spock's face as he says this, and Jim reels slightly as though he's been slapped. And then he smirks right back at the Vulcan.

"Straight to the point. Good. Now who the hell are you?"

Sherlock takes a closer look at the blond man in front of him before he answers. Young, captain of this vessel -maybe a ship, possibly a plane- gained the position under extreme circumstances. Hair has two layers of product, the most recent only applied ten minutes ago- it's still slightly wet. Definitely trying to impress someone, most likely the man whose body he now inhabits. His hand twitches, as if to move towards Sherlock before it stops, but it's almost an instinctive gesture, too used to wanting to touch and not being able to- _definitely_ in love with this body. Not just body, the mind as well; there's a look on his face that is akin to that of a stranded puppy. Clearly his second in command, if the call to the doctor was anything to go by. Why not call your immediate subordinate in a situation like this? And obviously a doctor, who else would work in a place called sickbay? He stops analysing the young captain before him and finally speaks.

"Not someone you'll have heard of, I assure you." A pause, and then, "The name's Sherlock Holmes, even if the body is not. Oh, but how did I get here? You clearly picked up a signal, but from what? Must be one of Mycroft's new cameras." Jim raises an eyebrow, and damn if he isn't mimicking Spock already, and stares at the Vulcan. He's heard of Sherlock Holmes, alright. The man was a twenty-first century symbol, the greatest detective there ever was, and then he'd been framed and thrown himself from the roof of a hospital and played dead for three years. Jim can't remember the specifics of that story, because knowing the history of almost everything is _Spock's_ job and Jim already feels lost without him.

"Captain James T. Kirk of the USS Enterprise, and _you_ are in the body of my first officer." Jim wants to strangle himself the moment the words are out his mouth - does this count as breaking the Prime Directive?

But the not-Spock, Sherlock, is too busy analysing himself to have paid any attention to Jim's words. He's pulling at his hair and then scrutinising his hands, and then running his hands over his face and earsbefore one hand clamps onto his side -Spock's heart, if Jim has his biology right- and his eyes widen comically in realisation.

"Interesting. The possibility of other life was always there, but I always assumed microbes at best and-" Jim drowns him out as he launches into some scientific speech, and mentally panics at the realisation that not only is this Spock's body, but it's equipped with the mind of someone equally as smart and twice as emotional as the Vulcan.

Spock's voice, louder than Jim has ever heard it, quietens abruptly and Jim is torn from his slightly destructive thoughts of _where the fuck is his first officer's mind then if he has a detective as a first officer,_ and both look to the doors of the transporter room as they swish open.

Sherlock begins his deductions as Jim decides that he's really not getting paid enough for this.

* * *

When Spock wakes, he's hit with a wave of alarm. Approximately ninety percent of it is his own. The rest is coming from the hand pressed to his forehead.

At first he assumes the hand belongs to his captain: there's blond hair attached to the head of the man and the hand is firm on his forehead, so whoever it was must be familiar enough with him that touch is disregarded as an issue. But then he realises that the hair is too long to be Jim's, remembers that Jim daren't touch him despite his obvious feelings, and Spock hasn't told him he knows, so there's no reason for Jim to be this familiar with him. And most importantly, despite the touch, Spock is only getting the barest of impressions of this man's emotions. With skin to skin contact, he should be able to know the words rushing through his mind at this very moment.

He sits up quickly, grasping the man's wrist where his jumper begins, to avoid contact, and removes the hand from his head.

"Kindly refrain from initiating contact with me." The man, a human no younger than forty, pulls his hand back with a brief look of hurt flashing across his face. Spock ignores it, glances around the room for any indication of where he is, and is nearly struck speechless when he sees the Times newspaper -outdated, people don't generally use those newspapers any more dated September 29th 2012. He is an alien in a pre-warp earth; he now understands why the human is looking at him so curiously. But, when he puts one hand to his left ear, he feels only a curved ear where a point should be.

"You're an idiot, Sherlock, I told you to eat during the case! Knew you'd bloody well pass out when we got back." The man sounds exasperated, and Spock knows that this 'Sherlock' must be the body of the man who he seems to be inhabiting. He does not respond, is not really sure how to, and inwardly remembers all the materials needed for a tricorder. If he could manage to make one in 1930's America, he could definitely make one here. It was logical, then, that he find a computer to research whether the parts needed were available in pre-warp England.

"Laptop." Spock says aloud, and the man sitting on the arm of the settee simply sighs in exasperation before he leans over to a table and hands a device to him. Spock nearly drops it, the cause a combination of the lack of strength this human body has and the miscalculation of how heavy those computers were two hundred years earlier.

"Sherlock! You alright?" The name registers again with Spock's mind, and immediately he recalls the information associated with the name 'Sherlock'. If he is inhabiting the body of the Consulting Detective, then this man must be John Watson. Rather than explain the situation to the human, Spock decides it is logical to keep the act going to move things along quickly.

"I am well, Doctor Watson." The words surprise John, who expects a haughty 'fine', and the blond man keeps his eye on his flatmate as Spock opens up then laptop and quickly studies it. He figures out how to work it in under five seconds, and is pleased to see that web browsers have not changed much in the last two centuries. He is careful not to give anything away, ensures that he does not slip up in the slightest and, to John Watson, it looks like Sherlock Holmes is simply having another odd day.

"What are you looking for this time?"

"Several components needed to recreate a device I caught glimpse of a few days ago. Whilst I will have to use older, weaker metals in its construction, I have confidence I can successfully recreate the device in approximately three point seven days." Spock's response is automatic but vague, and he does his best to ignore the invasion of his personal space when the human leans over his shoulder to look at the screen. Allowing the action will keep up the pretence, and Spock has no wish to attempt to explain his situation to a human who has had no previous contact with an alien life.

"Exactly _what _device are you on about?"

"A device which you would term dull." Spock pauses; he can feel an oncoming headache that is a result of attempting to keep up mental shields he does not need, and knows he has no way of preventing or ignoring it. It will be the first headache he has had in nearly a decade. "I do not believe it would be of particular interest to you, Doctor Watson." The human looks at him quizzically, and Spock is sure that he cannot continue speaking, else suspicion will arise.

He decides that he will read contemporary articles of Sherlock Holmes, once the human is out of the way. Finally, with a look at his watch, the human steps completely out of Spock's vision and moves towards the doorway with a scoff of disbelief.

"Yeah well, I'm off to work. You've made me late enough as it is. Just…don't blow anything up this time. And don't use the kettle for any 'weaker' metals you may or may not need!" With a scornful tone that Spock feels the human uses often, Doctor Watson retreats down the stairs, and Spock is admittedly disappointed to find that he no longer possesses his superior hearing. It was logical that, with the body of a human, he would lose it. Yet the sensation is... odd, to say the least.

This marks the second time he's been trapped in a pre-warp earth with the task of recreating a tricorder from scratch. The first time, he had to put up with Jim's distracting sarcastic comments and bright smile as the days went on, and the makeshift tricorder that was produced from that endeavour was now laying on a shelf in Jim's quarters. This time, there is no Jim to help with the mannerisms and technology of pre-warp earth.

Illogically, he finds himself missing his friend.


End file.
